Crosslinked styrene-acrylate copolymers were synthesized and evaluated by swelling properties for oil-absorbency application. The effect of various polymerization conditions (crosslinking agent concentration, initiator concentration, monomer concentration, and polymerization temperature) were studied through oil-absorption tests using kerosene oil. The oil absorbency was influenced mainly by the degree of crosslinking and the hydrophobicity of the copolymer units. The effect of moisture and the types of acrylate were also investigated. The copolymer with a longer alkyl acrylate had higher oil absorbency in the order of stearyl acrylate (SA) > lauryl acrylate (LA) > 2-ethylhexyl acrylate (EHA). The oil absorbency of the lauryl methacrylate (LMA) copolymer was higher than that of the LA copolymer.